This invention relates to an apparatus for detecting the presence of oil in the vicinity of a water submersible pump, and more particularly, an apparatus which will shut down operation of the pump when oil is detected.
Electric utilities commonly use water submersible pumps in transformer vaults for dewatering the vaults. For example, if water accumulates in a transformer vault, it may short a power line causing substantial problems delivering electricity to a consumer. Accordingly, water submersible pumps are commonly placed in the transformer vault to pump out accumulated rainwater and the like which may seep into the vault to maintain the water below a particular level.
Transformers are normally filled with an oily fluid for lubricating and cooling the various components of the transformer. This oily fluid also has a tendency to leak from the transformer housing into the vault. There is a danger to the environment if the oily fluid is pumped with the water into a waste disposal tank or sewer, as such oily fluids usually contain compounds which are harmful to the environment. Further, if the oil admixes with the water and both are pumped to a treatment disposal facility, suitable separation equipment must be provided to separate the oil from the water so that water can readily be disposed of and the oil recycled, or at least stored in a toxic safe facility. Such separation equipment is an item of considerable expense to a utility.
Accordingly, this invention discloses an apparatus which is usable with a water submersible pump of the type used by an electric utility in a transformer vault to insure that only water is pumped from the vault and oil will be left behind. In this manner, the vault can be periodically cleaned to remove the oil alone without the requirement of separating it from water which, as indicated, can be quite expensive. Further, the oily fluids which are removed can be trucked directly to a toxic waste facility, or recycled directly without fear of water contamination.